Military Officials: 50,000 ISIS Fighters Have Been Killed

According to U.S. military officials, as many as 50,000 ISIS fighters have been killed on the battle field in Iraq and Syria, but the group is far from depleted.

"It's a large number. We've been conducting air strikes now for several years, over 16,000 by the Pentagon's count and we've had multiple Defense and Intelligence officials testify that ISIS has been sending as many as 1500 fighters per month over the last several years into Iraq and Syria," former advisor to Vice President Dick Cheney and Green Beret commander Michael Waltz said during an interview on Fox News about the numbers. "I'm glad we've killed a lot of them, but I think there's more behind that number and still a lot of work to be done."

"I think we've done a good job across the military and inter-agency of cutting some of those [fighter] supply lines, but ISIS has also shifted its strategy and gone to more of a franchise model where they have franchises so to speak in Libya, in different parts of the Middle East, in Afghanistan continues to grow. We can't forget the war that is ongoing over there," he continued. "ISIS has taken more of a diffused model and isn't concentrated quite so much."

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During a recent interview with CNN, President Obama said he was surprised at the capability of ISIS to take and control large swaths of territory, despite being warned by President Bush about the deadly consequences of leaving Iraq early.